In vivo (visible and UV) slit lamp densitography data on the aging human cornea and ocular lens will be performed on patients from the first through the ninth decade of life. These data will be correlated with the in vitro visible fluorescence data on the lens and cornea as well as with specific spectroscopic parameters (changes in transmission, fluorescence, phosphorescence, EPR spectra and triplet (phosphorescence) as well as fluorescence lifetime values) which are being measured in selected tissue samples and their protein and peptide extracts. These data should help characterize some of the biophysical changes associated with the aging process in the eye. Since certain photobiologic effects mimic and accelerate the aging process we will continue with our delineation of the mechanisms involved in direct photic and photosensitized ocular damage utilizing the foregoing spectroscopic evaluations as well as derivatization and GC mass spectrometry techniques on model compounds and purified lens peptides. We will continue our studies to evaluate direct photic and photosensitized damage to the retina in aphakic eyes, utilizing 3H and 14C labeled photosensitizing drugs and autoradiography. Concurrent with the aforementioned studies, we will continue with our attempts to correlate morphologic changes in these ocular tissues with our biophysical and clinical data.